Police questioned Avigdor Lieberman on Tuesday morning for approximately five hours as part of a corruption probe against him for the third time since he took office as Foreign Minister.

Police believe the Yisrael Beiteinu leader will need to be questioned once more before fraud squad detectives can complete their work and hand over material from the investigation to the State Prosecutor's Office.

The site of Lieberman's questioning has been kept secret by police, in an effort to prevent the media from covering the minister's arrival for questioning.

According to police estimates, meanwhile, material gathered in the probe thus far provides an evidential basis for charges of money laundering, fraud and breach of trust.

Investigators are also examining the possibility of adding bribery charges to the list.

On Sunday, Channel 2 revealed that the Yisrael Beiteinu leader has been questioned over suspicions of obstructing the probe against him. It reported that Lieberman is suspected of changing the names of straw companies he established in Cyprus, in concert with his partners, after he believed police had become aware of their identities.